Electromechanical performance and membrane stability of novel ionic polymer transducers constructed in the presence of ionic liquids
2009
Ionic polymer transducers (IPT) are a class of devices that leverage electroactive polymers (EAP), specifically
electrolyte-swollen ionomeric membranes, to perform energy conversions. Energy transformation from input to output is
referred to as transduction and occurs between the electrical and mechanical domains. The present study expands on IPT
investigations with a novel series of sulfonated polysulfones (sBPS), with specific interest in the effect of polymer
topology on actuator performance. A hydrophilic ionic liquid was combined with a series of sBPS through a casting
method to create hydrated membranes that contained target uptakes ( f ) of the diluent. The ionic liquid's hydrophilic, yet
organic nature raised the issue of its degree of compatibility and miscibility with the microphase separated domains of
the host ionomeric membrane. Initial studies of the ionomer - ionic liquid morphology were performed with synchrotron
small angle X-ray scattering (SAXS). The effective plasticization of the membranes was identified with dynamic
mechanical analysis (DMA) in terms of varied storage modulus and thermal transitions with ionic liquid uptake.
Electrical impedance spectroscopy (EIS) was employed to quantify the changes in ionic conductivity for each sBPS
ionomer across a range of uptake. Combined results from these techniques implied that the presence of large amounts of
ionic liquid swelled the hydrophilic domains of the ionomer and greatly increased the ionic conductivity. Decreases in
storage modulus and the glass transition temperature were proportional to one another but of a lesser magnitude than
changes in conductivity. The present range of ionic liquid uptake for sBPS was sufficient to identify the critical uptake
( f c ) for three of the four ionomers in the series. Future work to construct IPTs with these components will use the critical
uptake as a minimum allowable content of ionic liquid to optimize the balance of electrical and mechanical properties
for the device components.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
3
Citations
NaN
KQI